Various possibilities are known for reducing the pushing force for vacuum cleaner nozzle arrangements. Thus, published German patent application DE-OS No. 31 00 164 discloses a vacuum cleaner nozzle which is provided with very large air intake channels for the suction edges of the suction channel. On the outside of the suction channels, supporting surfaces are provided with are not charged with a force of reduced pressure. In this way, a flotation of the nozzle of the vacuum cleaner on the textile surface is possible so that the pushing force is reduced.
Further, German Pat. No. 28 46 847 discloses vacuum cleaner nozzle arrangements which include: a connecting piece easily movable by means of wheels; a suction channel; and, an additional intermediate piece located between the suction channel and the connecting piece and articulately connected to both. This is intended to prevent lifting or a slanting of the suction edges of the suction channel.
Such nozzle arrangements must, nevertheless, additionally have angle limiters in the tilting joint between the connecting piece and intermediate piece to prevent a doubling-over of the last member of the articulated chain, namely, the nozzle.
Further, configurations of this kind all exhibit a progressive friction characteristic. This means that the larger the resistance of the carpet, the disproportionately larger is the friction force.
The friction force always develops a moment that is directed towards the carpet. Therefore, the pushing force increases sharply.